WASHINGTON (CNN) -- Despite a hardline U.S. policy, there is no reason why federal officials can't negotiate directly with pirates who are holding a U.S. captain hostage off Somalia, a counterterrorism expert said Thursday.

Pirates have been plaguing commercial shipping vessels in the waters off the coast of east Africa.

Nor is there anything to stop an independent party from paying for his release, said Juan Carlos Zarate, who served as deputy national security adviser for combating terrorism under former President George W. Bush.

"The U.S. has a very clear policy of no concessions; that's different than no negotiations," said Zarate, now is a senior adviser to the Center for Strategic and International Studies in Washington.

The U.S. policy against concessions translates into a policy against paying for the release of hostages, he said.

"That means no ransoms, nothing of value in return for the safe release of hostages," he said.

But, he added, "It's also important to note that there's nothing in U.S. policy that restricts family members or private companies -- like a shipping company -- to actually pay a ransom. There's nothing that the U.S. government can do other than potentially to prosecute if that money is going to a known terrorist organization, which is a fine line."

Nevertheless, he said it is U.S. government policy to discourage private companies from making payments to hostage takers.

"The U.S. has a very clear sense that, if you start to pay ransoms, you in essence create an industry for kidnapping," he said.

"And, frankly, it's why you see an uptick in the piracy problem in East Africa. It's a for-profit venture. It's very lucrative at low cost for the pirates and it's, in part, fueled by the fact that shipping companies in other countries have been paying ransoms for the release of ships, cargo and personnel."

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"I don't see or forecast the use of massive force inadvertently because of the potential for hurting our citizen," he said, referring to Richard Phillips, the captain of the Maersk Alabama who was taken hostage after four gunmen boarded it on Wednesday.

"And so I think this is going to take a while, and it may involve some third-party negotiations."

Though he approves of the government's handling of the situation so far, Zarate said the situation not an easy one.

"This, to a certain extent, is the U.S. government's nightmare scenario," said Zarate, who oversaw the U.S. government's counterterrorism strategy from 2005 to 2009.

"We had always planned for, but hoped that this kind of situation wouldn't happen -- where a U.S. vessel was taken or a U.S. citizen was taken in those waters," he said.

He called the standoff "a classic hostage situation, which is difficult to resolve. It is certainly difficult to resolve on the high seas where we have limited levers to play." iReport.com: How should the U.S. respond?

Zarate said the hostage holders appear to be in the stronger position, though at first glance -- four men holding a fifth aboard a 28-foot powerless lifeboat in the ocean hundreds of miles from shore -- that may not appear to be the case.

"I think they have the upper hand, in part, because we value the life of our citizens," he said. "They may not value their lives as much, and they may not be using the same rational calculus that we would in this situation."

But, he said, the pirates may not be able to turn that advantage into victory.

"I think we'll find a way out of this. I think the FBI hostage negotiators, the naval personnel on scene and others will find a way of negotiating their way out of this. They're professionals; they know how to do that. But it's difficult."